Savings Plans, Pension Plans and Other Postretirement Employee Benefits (Change in Benefit Obligation, Plan Assets and Funded Status for Company-Sponsored Benefit Plans and Obligations) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit Obligation	$ 395,086
Medicare Part D Subsidies Received	700	600
Benefit Obligation	418,251	395,086
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets	329,064
Fair Value of Plan Assets	312,158	329,064
Amounts recognized in the consolidated balance sheets [Abstract]
Current Liabilities	8,172	9,517
Noncurrent Liabilities	163,116	129,124
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Funded Status of Plan	(106,093)	(66,022)
Amounts recognized in the consolidated balance sheets [Abstract]
Current Liabilities	(1,712)	(1,708)
Noncurrent Liabilities	(104,381)	(64,314)
Net Amount Recognized	(106,093)	(66,022)
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Funded Status of Plan	(65,195)	(72,619)
Amounts recognized in the consolidated balance sheets [Abstract]
Current Liabilities	(6,460)	(7,809)
Noncurrent Liabilities	(58,735)	(64,810)
Net Amount Recognized	(65,195)	(72,619)
Benefit Obligation [Member] | Pension Plans, Defined Benefit [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit Obligation	395,086	399,875
Service Cost	4,456	4,633
Interest Cost	21,325	21,649
Plan Amendments	0	0
Actuarial Loss (Gain)	27,916	106
Closures and Special Termination Benefits	0	(432)
Medicare Part D Subsidies Received	0	0
Benefits Paid	(30,532)	(30,745)
Benefit Obligation	418,251	395,086
Benefit Obligation [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit Obligation	72,619	82,074
Service Cost	446	415
Interest Cost	3,486	3,972
Plan Amendments	(5,805)	0
Actuarial Loss (Gain)	(913)	(6,147)
Closures and Special Termination Benefits	0	65
Medicare Part D Subsidies Received	741	552
Benefits Paid	(5,379)	(8,312)
Benefit Obligation	65,195	72,619
Fair Value of Plan Assets [Member] | Pension Plans, Defined Benefit [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefits Paid	(30,532)	(30,745)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets	329,064	318,590
Actual Return on Plan Assets	2,500	38,863
Contributions by Employer	11,126	1,729
Spin-off of Clearwater Paper	0	627
Fair Value of Plan Assets	312,158	329,064
Fair Value of Plan Assets [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefits Paid	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets	0	0
Actual Return on Plan Assets	0	0
Contributions by Employer	0	0
Spin-off of Clearwater Paper	0	0
Fair Value of Plan Assets	$ 0	$ 0